The translation of the "Glowing Item Frame" string, in EL-GR, has an irrelevant meaning. More specifically, the El-GR text, has the meaning of, "Frame for Glowing Items" instead of  "Glowing Item Frame".

How to replicate:

1. Change to or be sure that the Greek (EL-GR) Language - is selected.
2. Obtain or find the Glowing Item Frame - In the inventory or the craftign table.
3. Hover over the item in the inventory /Recipe Book (Crafting table) or select the item in the hotbar.
4. See the name of the item in EL-GR, and translate it to English (Translates to: Frame for Glowing Items).
5. Conclude that the translation of the item in EL-GR, since it has a diffrent meaning / translation to English, from the Expected ("Glowing Item Frame")

How to Resolve the Issue:

Replace the wrong translation of the item, with a / the correct one, inside of the "texts/EL-GR.lang" file -> Possible Correct Translation: " Φωσφωριζέ Κορνίζα Αντικειμένου"